Note: Descriptions are shown in the official language in which they were submitted.
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A DEVICE FOR ELECTRO-CHEMICAL WATER OR WATER SOLUTIONS
BACKGROUND
The invention pertains to the electrochemical treatment of water and salt
water
solutions and more specifically to changing their oxidation-reduction
properties. The
invention also pertains to water purification and disinfection, cathode
softening, and
washing and disinfectant liquids.
Water processing devices are known in the art. One device for electrochemical
water
processing contains an external cylindrical electrode with an inside electrode
and
semi-permeable diaphragm between the electrode separating the electrode space
into external and internal electrode chambers. (Japanese Patent Application
No. 1-
104387, class C02F 1/46, 1989, Russian Patent No. 2078737, class CO2F 1/46,
1997].
However, achieving desired water or water solution characteristics using these
devices is difficult due to the limited functional resources of the devices
which make
it impossible to affect compounds with oxidation-reduction potentials in a
wide range
of different pH values.
One device for water or solution processing contains the external electrode in
the
shape of a hollow cylinder with an internal cylinder-shaped electrode placed
coaxially
within it. The semi-permeable diaphragm is placed coaxially between the
electrodes,
separating the electrode space into internal and external electrode chambers,
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wherein the internal electrode chamber is directly connected by a channel for
liquid
supply. [Russian Patent No. 2145940, class C02F1/461, 2000].
Achieving desired water or water solution characteristics using this device is
difficult,
due to the limited ability of the device to organize the hydrodynamic currents
in the
liquid, making it impossible to achieve a high distilled water current with
the required
values of mineralization.
The most similar device in terms of its properties to the instant invention is
a device
for electrochemical water or water solutions processing which contains an
external
pipe-shaped electrode with an inner electrode disposed inside and a semi-
permeable diaphragm separating the electrode space into internal and external
electrode chambers; wherein the external chamber, through the holes on the
side
surface of the external cylindrical electrode, is connected to the incoming
and
outgoing channels and the internal electrode has at least one hole connecting
the
inner chamber with the channel for water removal. [Russian Patent No. 2132821
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C02F1/46, 1999].
Achieving the desired water or water solution characteristics is difficult
using this
device due to the limited resources of the device, making it impossible to get
compounds with the required oxidation-reduction potentials in a wide range,
low
productivity and complex installation and repair.
There is therefore a need for an electrochemical water and water solution
processing
device with high productivity. It is an object of the present invention to
increase
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productivity, widening the range of the received pH and oxidation-reduction
potentials of processed water, increase safety, increase the operational
lifespan of
the device; decrease installation and repair labor, and reduce energy
consumption
while operating the device. Finally it is an object of the present invention
to perform
these functions using a compact device.
SUMMARY
In order to achieve the objects of the invention, the device for electro-
chemical water
or water solutions processing contains an external electrode in the shape of a
hollow
cylinder with a cylinder shaped internal electrode inside. A coaxially placed
semi-
permeable diaphragm is disposed between the electrodes, separating the
electrode
space into internal and external electrode chambers. In the upper part of the
side
wall of the external electrode, a hole connects the external electrode chamber
with a
channel for liquid removal. In the upper part of the internal electrode at
least one
hole connects the internal electrode chamber with the channel for removing
liquid.
The internal electrode chamber is directly connected to the channel for liquid
supply
and the internal electrode is constructed with a flat wall in its lower
dimension.
In one preferred embodiment of the invention, the external electrode, internal
electrode and diaphram are fixed at a lower flange, where a channel has been
made
for liquid supply, connected to the internal electrode chamber. In another
preferred
embodiment of the invention, the internal electrode and diaphram are fastened
at the
top with a lid where the diaphragm is positioned with the aid of slot joints
and a
hermetic rubber seal.
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In another preferred embodiment, the internal electrode has a conical shape at
the
end inserted into the external electrode.
In another preferred embodiment, the internal electrode is made in the shape
of a
hollow cylinder with at least one plug placed inside to hermetically seal the
internal
cavity under the hole connecting the internal chamber with the canal for
removing
the liquid.
In another preferred embodiment, the electrode is a compound of two parts,
wherein
the upper part comprises at least one hole connecting the internal chamber
with the
channel for removing the liquid.
In another preferred embodirrient, the parts of the internal electrode are
joined
together with the help of a mechanical joint, for example a threaded means.
In another preferred embodiment, in the low part of the sidewall of the
external
electrode there is at least one extra hole connecting the external electrode
chamber
with the liquid supply channel.
In another preferred embodiment, the internal electrode comprises the anode
and
the external electrode comprises the cathode.
In another preferred embodiment, the internal electrode is fixed with the help
of a pin
or a bolt at either or both the lower and upper flanges.
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In another preferred embodiment, there is a circular hole in the lower flange
which
creates a channel for the liquid supply into the internal electrode chamber.
In this
embodiment there is at least one horizontal channel for the liquid supply
connected
with the channel for the liquid supply into the inner electrode chamber.
In another preferred embodiment, the semi-permeable diaphragm is made of
ceramic based on zirconium oxides or textile.
In a final embodiment of-the invention, the semi-permeable diaphragm may be
ultra
filtering, micro filtering, or nano filtering.
FIGURES
Figure 1 is a cut-away side view of the device for the electro-chemical water
or water
solution processing.
Figure 2 is a cut-away side view of the device for the electro-chemical water
or
water-solutions processing, with an extra channel for entering fluid.
Figure 3 is a cut-away side view of internal electrode in the shape of a
hollow
cylinder.
DETAILED DESCRIPTION
Referring to Fig 1, the device for the electro-chemical water or water-
solutions
processing contains an external electrode 1 in a shape of a hollow cylinder.
An
internal electrode 2 is disposed inside the external electrode 1, and a semi-
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permeable diaphragm 3 is disposed between the electrodes separating them into
internal 4 and external 5 electrode chambers.
The upper part of the side surface of the external cylindrical electrode 1
comprises a
hole 6, connecting the external electrode chamber 1 with a first exit channel
7. In the
internal electrode 2 there is at least one hole 8 connecting the internal
chamber 4
with a second channel 9 for removing the liquid. The internal chamber 4 is
connected
by a circular channel 10 with a horizontal channel 11 for the processed liquid
supply.
The external electrode 1, internal electrode 2 and diaphragm 3 are fixed
steadily and
coaxially with the help of a lid 12 and lower flange 13. The lower flange 13
may be
made of compound parts.
The diaphragm 3 is fixed in position with the help of slot joints in the lower
flange 13
and lid 12, and has rubber seal circles on the face. The external electrode 1
is
placed at the lower flange 13 and is attached by depressing the lid 12. The
external
electrode 1 may be fixed at the lower flange 13 by welding the external
electrode 1 to
the lower flange 13 in the shape of a flat circle. The joint may also be
reinforced with
the help of a boit.
The internal electrode 2 is fixed at the lower flange 13 with the help of a
pin 14, and
fixed in the lid 12 with the help of slot joints and a fastening hollow bolt
19.
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The diaphragm 3 may be made of ceramic on the basis of zirconium oxides or
textile. Additionally, diaphragm 3 may be ultra filtering, micro filtering, or
nano
filtering.
To make the external electrode chamber 5 seal hermetically, sealing elements
15
are placed on the. lid 12 and flange 13.
Referring to Fig 2, an extra hole 16 is disposed on the side surface of the
external
cylindrical electrode 1 connecting the external electrode chamber 5 with a
third
channel17.
Depending on the functional use of the device, the internal electrode 2. may
be
cathode, and the external electrode 1 anode; the internal electrode chamber 4
may
by a working one, and the external electrode chamber 5 an assisting one.
The internal electrode 2 may be made with a conical shape to one end and may
consist of two parts: an upper 2/ and a lower 2// (as shown in Fig 1). In this
embodiment, the holes 8 are made in the upper part of the pivot electrode 2//.
The
upper 2/ and the lower 2// parts of the electrode 2 may be joined together in
different
ways, including by threaded joints. In another preferred embodiment, the inner
electrode 2 is made in the shape of a hollow cylinder with at least one plug
18 placed
inside, sealing the inner cavity under the hole 8. The internal electrode 2
may also
have external threadding at the ends for fastening the lid 12 and the flange
13.
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In order to actuate the device, the horizontal channel 11 is used to supply
processed water or salt solution to the device. The third channel 17 is used
to
supply a salt solution, and the second channel 9 is used for removing the
processed
anolitic liquid. The first exit channel 7 is used for removing catolite or
salt solution.
To produce anolit and catolit, the chloride sodium solution is sent through
the
horizontal channel 11. The circular channel 10 introduces the solution into
the
internal electrode chamber 4. Voltage is applied to the electrodes, wherein
the
internal electrode 2 is anode and the external electrode 1 is cathode. Under
pressure, the solution goes through the semi-permeable diaphragm 3 into the
external electrode chamber 5. While the device is working on the external and
internal surfaces of the diaphragm 3, oppositely charged ion currents occur.
The
potential difference between these charged currents increases the intensity of
the
electrical field at the diaphragm 35-50 W/cm2. As a result, the activity of
the ions in
the pores of the diaphragm increases and the electrical resistance of the
device
decreases. As a result, an electro-activated solution anolit appears, which is
removed through the second channel 9, and a solution catolit, which is removed
through the first channel 7. If the device is made with an additional hole 16
and third
channel 17, chloride sodium can be also supplied through the third channel 17.
In order to produce a disinfected solution, water is supplied through the
horizontal
channel 11, which then goes into the internal electrode chamber 4. 30%
solution of
chloride sodium is supplied through the third channel 17, which circulates in
the
cavity of the external electrode chamber 5. The first internal channel 7 is
used for
removal of this solution into a salt solution container, which is used as a
reservoir of
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the solution and supplies it back to the device through the third channel 17.
Water,
having gone through the inner electrode chamber 4, is removed through the
second
channel 9 in the form of anolit.
The polarity of the electrodes can vary; the external electrode 1 may be
cathode and
the internal electrode 2-anode, and vice-versa. Due to this variable electrode
polarity, problems with cathode precipitation and salt precipitation on the
membrane
are avoided, making the device safe and long lasting. Cathode precipitatiori,
which
may appear during the working process, can be removed by changing the
electrode
polarity, making the device easier to use.
The device is more compact because the internal electrode 2 is made with a
flat wall
in the lower part and the internal electrode chamber 4 is connected directly
with the
circular channel 10. At the same time, the heights of the external and
internal
electrodes as well as the diaphragm differ only in the size of the fastening
slots.
Therefore, the entire surface of the electrodes and diaphragm is used in the
electro-
chemical process, which increases the productivity of the device and economy
of the
electrode materials. These characteristics enable the pH range of the
processed
water properties to widen.
The direct connection of the internal electrode chamber 4 with the circular
channel
10 ensures uniform current flow through the electrode chambers; a high degree
of
mixing in the chambers, and uniform electro-chemical liquid processing,
including
processing all micro volumes of water in the diffuse part of the double
electric layer
on the phase border "electrode-electrolyte."
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The diaphragm 3, placed between the anode and cathode, plays the most
important
role in creating the electrical resistance of the device. The effective use of
the
diaphragm's surface decreases electrical resistance, making the device more
energy
efficient. By changing the permeability of the diaphragm, solutions with
different pH
values and oxidation-reduction potentials are possible. -
The hole made in the upper part of the internal electrode 2 connecting the
second
channel 9 for processed liquid removal, and the internal electrode 2 can be
made
with a solid wall in its lower part, and a direct connection between of the
internal
electrode chamber 4 with the circular channel 10. This permits the internal
electrode
chamber 4 to be used in electrochemical processing. Compared with existing
devices, the processed water additionally goes inside the hollow internal
electrode 2.
After the water is processed and enters hole 8, it slows down and is stirred.
Water
flowing into the second channel 9 creates turbulent stirring. This process
prevents
the formation of stagnant zones at the exit of the internal electrode chamber
4. It
also decreases the number of stagnant zones at the entrance and exit of the
anode
chamber and makes a more effective use of the diaphragm surface.
The design of the device results in a decreased number of compressed parts,
making the device safer.
The installation and repair of the device is very easy. With the help of
slots,
diaphragm 3 is placed vertically in the lid 12, a pin 14 is screwed into the
electrode 2,
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then the parts are fastened by turning the bolt at the bottom of the pin 14
and
adding a fastening bolt 19.
INDUSTRIAL APPLICATION
Construction of the device
The diameter of the interior surface of the external electrode is 34 mm. The
diameter
of the working part of the interior electrode is 16 mm. The space between the
electrodes is 9 mm. These measurements provide excellent conditions for all
volumes of processed solution or water to interact with the surface of the
diaphragm.
The diaphragm is made of ceramic. It may also be made of other materials that
are
resistant to an extreme environment. The diaphragm may have different
thicknesses
and permeability depending upon the characteristics of the required solutions.
The
cathode of the device is made of stainless steel, titanium, glass carbon, acid
proof
materials good at electrical conduction and niobium. The cathode is covered
with
platinum, iridium, ruthenium and cobalt oxides as well as other materials.
Anode is
made of titanium, niobium, tantalum, graphite and covered with platinum,
iridium,
ruthenium and other materials' oxides.
When using the device, it is possible to obtain solutions with pH values from
2 to 12
and oxidation-reduction potentials from -950 mV to +1200 mV. In the following
table,
characteristics of the instant device are compared with analogous devices
currently
produced.
Table: Parameters and characteristics of the devices used for electro chemical
water processing
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Parameters Devices
Analogous Presented
Volumetric current speed, cm3/s 2,8-8,3 27- 35
Linearity current speed, cm/s 5,8-24 25-64
Time of water processing, s 0,8-3 0,3-0,75
Current intensity, amp 3-8 1,5-30
Voltage, w 10-24 30-120
Water mineralization, gm/I 0,5-5,0 0,1- 5,0
Specific energy output, kI/I 360-2880 40-470
Amount of the processed liquid, I/hour 60 120
Recourse for the continual work, h 15000 40000
The table displays the increased performance characteristics of the instant
device
compared with similar existing devices.
By comparison with Russian Patent No. 2145940, which has a volumetric current
speed of 5.5 cm3/s, voltage of 7-20 W, current intensity from 5 to 10 amps,
and
achieved mineralization is 0,27-0,7 gm/l; the instant invention has a
volumetric
current speed of 27-35 cm3/s, a current intensity of 1.5 - 30 amps, voltage of
30 -
120 W, and 0,1-5 gm/I mineralization.
The operation of the instant invention has a volumetric current speed 5 times
faster
than that of Russian Patent No. 2145940. The comparison of the values of the
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volumetric current speed and mineralization shows the improved technical
results of
the instant device over those currently in the art.
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